Severely disabled children born in Australia are being denied access to the National Disability Insurance Scheme (NDIS) because their parents are New Zealand citizens.

Key points:

A special visa category is preventing some children from accessing NDIS

Parents are being forced to pay NDIS tax but cannot access support

Advocates describe situation as 'clear case of discrimination'

In a situation disability advocates have described as a "clear case of discrimination", children born in Australia to New Zealand parents or on special visas cannot access the scheme because of government rules.

That is exactly the case for seven-year-old Toby Bensemann, who was born premature in Sydney in 2008 and now has autism.

His mother Angela said with the help of early intervention her son had gone from strength to strength.

"Toby has just flourished, he exceeded all our expectations in his first couple of years at school," she said.

"We went from having this little 24-weeker who we were told probably wouldn't survive, and if he did he would be severely disabled, to having this wee boy who was going to mainstream school."

Ms Bensemann wants her son to continue to get early intervention but says she has been told he will not be eligible for help when her area is transferred to the NDIS because he is not yet aged 10 and consequently not a citizen.

NDIS access refusal 'clear case of discrimination'

Ms Bensemann said her family paid the NDIS levy as part of their Australian taxes and it was discriminatory to refuse them access to scheme.

"I feel broken to be honest because I've got this wee boy who desperately needs help to learn how to cope in society and with his emotions, and I just feel that all these doors have been closed on us," she said.

"The simple fact is if you pay that levy you should be able to access the benefits of that service."

New Zealand Labour MP Phil Goff said it was a clear case of discrimination.

It's a totally unfair situation. Nobody can justify that.

Phil Goff, New Zealand Labour MP

Mr Goff was foreign minister in Helen Clark's government in 2001 when John Howard ushered in sweeping migration changes that affected New Zealanders.

The migration changes were an attempt to limit New Zealand citizens coming to Australia and immediately accessing welfare, or citizens of other countries using New Zealand as a stepping-stone country to migrate to Australia.

"Australia wanted to put a curb on any costs that might be incurred by the Australian government in relation to New Zealanders working in Australia," Mr Goff said of the changes.

At that time, a new visa called the Special Category Visa (subclass 444) was introduced.

More than 626,000 New Zealand citizens are now living in Australia under that visa. Although they may be living here for decades, the visa is classified as a temporary visa.

"Under the Special Category Visa, any New Zealander who doesn't have a criminal record can work and live in Australia on an ongoing basis," Mr Goff said.

"We've got people who have gone to Australia obviously with the intention of living permanently in Australia, their kids are born in Australia, those kids are brought up in Australia, but their kids are not given citizenship on birth, not until they're 10 years old.

"These are people that for all intents and purposes are Australians.

"I think the really unfair thing is it is called an insurance scheme and every Kiwi working in Australia pays their premium — 0.5 per cent of their income — to the Australian Government to get disability protection … you're paying your premium, but you can never claim under the scheme.

"That's a totally unfair situation. Nobody can justify that."

Mr Goff raised the matter directly with Malcolm Turnbull when the Prime Minister visited New Zealand late last year.

A spokesperson for Disability Services Minister Christian Porter said that "governments have agreed that people with disability who are currently receiving supports but who are ineligible for the NDIS will not be disadvantaged".

"In these cases, governments will continue to support them outside of the NDIS either through continuing these programs or by alternative arrangements," the spokesperson said.

"Where the support a person is receiving is from a Commonwealth program, support will continue to be available within the Information, Linkages and Capacity Building (ILC) policy.

"In NSW where a state-run program may cease, the Commonwealth has agreed people will be able to receive continued support through ICC.

"The ICC will be rolled out prior to transition of an area to NDIS. Local area coordinator support to help people on the ground will also be available well before transition starts."

But a group of Labor MPs have been advocating on the issue.

One of those MPs is Clare O'Neal, the member for Hotham in Melbourne's north, who said she had been approached by several Kiwis living in her electorate who had been denied access to the NDIS.

"We don't really know how many New Zealanders are being affected by this problem, but I've certainly been contacted by quite a few New Zealanders in this situation," Ms O'Neal said.

"So they've lived in Australia for a long time, they've paid taxes, they've worked for many years but they're not able to access the special supports that you might expect and that often includes the NDIS."

'Height of hypocrisy': advocates

Disability advocates including Suresh Rajan, president of the National Ethnic Disability Alliance, are also taking up the cause.